Differential effects of approach bias and eating style on unhealthy food consumption in overweight and normal weight women

Virtual reality assessment of a high-calorie food bias: Replication and food-specificity in healthy participants

BACKGROUND

Theoretical models and behavioural studies indicate faster approach behaviour for high-calorie food (approach bias) among healthy participants. A previous study with Virtual Reality (VR) and online motion-capture quantified this approach bias towards food and non-food cues in a controlled VR environment with hand movements. The aim of this study was to test the specificity of a manual approach bias for high-calorie food in grasp movements compared to low-calorie food and neutral objects of different complexity, namely, simple balls and geometrically more complex office tools.

METHODS

In a VR setting, healthy participants (N = 27) repeatedly grasped or pushed high-calorie food, low-calorie food, balls and office tools in randomized order with 30 item repetitions. All objects were rated for valence and arousal.

RESULTS

High-calorie food was less attractive and more arousing in subjective ratings than low-calorie food and neutral objects. Movement onset was faster for high-calorie food in push-trials, but overall push responses were comparable. In contrast, responses to high-calorie food relative to low-calorie food and to control objects were faster in grasp trials for later stages of interaction (grasp and collect). Non-parametric tests confirmed an approach bias for high-calorie food.

CONCLUSION

A behavioural bias for food was specific to high-calorie food objects. The results confirm the presence of bottom-up advantages in motor-cognitive behaviour for high-calorie food in a non-clinical population. More systematic variations of object fidelity and in clinical populations are outstanding. The utility of VR in assessing approach behaviour is confirmed in this study by exploring manual interactions in a controlled environment.

Test-retest reliability of a smartphone-based approach-avoidance task: Effects of retest period, stimulus type, and demographics

The approach-avoidance task (AAT) is an implicit task that measures people's behavioral tendencies to approach or avoid stimuli in the environment. In recent years, it has been used successfully to help explain a variety of health problems (e.g., addictions and phobias). Unfortunately, more recent AAT studies have failed to replicate earlier promising findings. One explanation for these replication failures could be that the AAT does not reliably measure approach-avoidance tendencies. Here, we first review existing literature on the reliability of various versions of the AAT. Next, we examine the AAT's reliability in a large and diverse sample (N = 1077; 248 of whom completed all sessions). Using a smartphone-based, mobile AAT, we measured participants' approach-avoidance tendencies eight times over a period of seven months (one measurement per month) in two distinct stimulus sets (happy/sad expressions and disgusting/neutral stimuli). The mobile AAT's split-half reliability was adequate for face stimuli (r = .85), but low for disgust stimuli (r = .72). Its test-retest reliability based on a single measurement was poor for either stimulus set (all ICC1s < .3). Its test-retest reliability based on the average of all eight measurements was moderately good for face stimuli (ICCk = .73), but low for disgust stimuli (ICCk = .5). Results suggest that single-measurement AATs could be influenced by unexplained temporal fluctuations of approach-avoidance tendencies. These fluctuations could be examined in future studies. Until then, this work suggests that future research using the AAT should rely on multiple rather than single measurements.

Testing the effectiveness of a mobile approach avoidance intervention and measuring approach biases in an ecological momentary assessment context: study protocol for a randomised-controlled trial

INTRODUCTION

Unhealthy eating behaviour is a major contributor to obesity and related diseases and is associated with a behavioural bias to approach rather than avoid desired foods, as measured with reaction time tasks. Approach-avoidance interventions (AAIs) have been proposed as a way to modify food evaluations and help people to eat in accordance with their dietary goals. Mobile implementations of AAI might be easily accessible, low threshold interventions, but their effectiveness has not been established yet.

METHODS AND ANALYSIS

Participants who aim to change their eating behaviour are randomised to intervention or control groups. They complete six sessions of a smartphone-based AAI, in which they push (ie, avoid) or pull (ie, approach) personalised food images. Intervention group participants always avoid foods that they personally want to eat less often and approach foods that they personally want to eat more often. In the control group, images are paired equally often with both response directions. To evaluate contextual and dynamic intervention effects, ecological momentary assessment (EMA) is measured throughout, with questions about food intake, hunger, stress, emotions, eating intentions, food craving and impulsivity twice a day. Additional EMA preintervention and postintervention measures are administered before and after the intervention phase (4 days each) with a 1-day follow-up EMA 4 weeks after the intervention. Multilevel models will examine the temporal covariance between approach bias and self-reported variables as well as short-term and long-term intervention effects on approach bias, food intake and craving.

ETHICS AND DISSEMINATION

The study was approved by the Ethics Committee of the University of Salzburg. Results will be published in peer-reviewed scientific journals and presented at scientific conferences.

TRIAL REGISTRATION NUMBER

German Clinical Trials Register DRKS, registration number DRKS00030780.

Differential Orbitofrontal Cortex Responses to Chocolate Images While Performing an Approach-Avoidance Task in the MRI Environment

Background: Chocolate is one of the most frequently craved foods, and it often challenges self-regulation. These cravings may be underpinned by a neural facilitation of approach behavior toward chocolate. This preregistered study investigated the behavioral and neural correlates of such a bias using functional magnetic resonance imaging (fMRI) and reaction times (RTs). Methods: A total of n = 30 frequent chocolate eaters performed a relevant-feature approach-avoidance task (AAT) in the MRI scanner using buttons to enlarge (approach) or to shrink (avoid) pictures of chocolate and inedible control objects. We tested (a) whether implicit RT-based approach biases could be measured in a supine position in the scanner, (b) whether those biases were associated with activity in reward-related brain regions such as the insula, amygdala, striatum, and orbitofrontal cortex (OFC), and (c) whether individual RT-based bias-scores correlated with measures of chocolate craving. Results: Behaviorally, we found a highly reliable approach bias toward chocolate, defined by faster RTs in the compatible conditions (approach chocolate, avoid objects) compared to the incompatible conditions (avoid chocolate, approach objects). Neurally, this compatibility effect involved activity in the left medial OFC, a neural response that was positively correlated with individual approach bias scores. Conclusions: This study shows that the relevant feature AAT can be implemented in an fMRI setting in a supine position using buttons. An approach bias toward chocolate seems related to medial OFC activation that might serve to devalue chocolate when it has to be avoided. Our demonstration of neural and behavioral approach biases for chocolate underscores the need for stimulus-specific cognitive trainings to support healthy consumption and successful self-regulation.

EXPRESS: Reliability and Convergence of Approach/Avoidance Bias Assessment Tasks in the Food Consumption Domain

Theories of motivation posit that people will more readily approach positive or appetitive stimuli, and there has been growing interest in the relationship between biases in approach and avoidance behaviours for food cues and food craving and consumption behaviour. Two paradigms commonly employed by research to investigate this relationship are the Approach Avoidance Task (AAT) and the Stimulus Response Compatibility Task (SRCT). However, it is yet to be determined whether the measures yielded by these tasks reflect the same processes operating in the food craving and consumption domain. The present study examined the internal reliability and convergence of AAT and SRCT paradigms in their assessment of biased approach to unhealthy compared to healthy food stimuli, and whether the measures yielded by the AAT and SRCT paradigms demonstrated associations with individual differences in food craving and eating behaviour. One hundred and twenty-one participants completed an SRCT, an AAT using an arm movement response mode, and an AAT using a key-press response mode. The measures yielded comparable and acceptable levels of internal consistency, but convergence between the different task bias scores was modest or absent, and only approach bias as measured with the AAT task using an arm movement response mode was associated with self-report measures of eating behaviour and trait food craving. Thus, tasks did not converge strongly enough to be considered equivalent measures of approach/avoidance biases, and the AAT task using an arm movement response seems uniquely suited to detecting approach biases argued to characterise maladaptive eating behaviour and craving.

Healthiness matters: Approach motivation for healthy food in overweight and obese individuals

It is well documented that approach tendencies for appetitive substances play a role in certain unhealthy patterns of consumption. However, it remains uncertain whether overweight individuals differ from healthy-weight individuals in terms of their tendency to approach unhealthy foods. Thus, the present study aimed to empirically test the hypothesis that overweight individuals are characterised by an elevated behavioural tendency to approach unhealthy food, rather than healthy food, as compared to healthy-weight individuals. Participants were forty-one overweight individuals (Mean BMI = 30.40 kg/m²) and forty-five healthy-weight individuals (Mean BMI = 22.17 kg/m²) aged between 17 and 47. They completed an Approach-Avoidance Task to assess behavioural approach-avoidance tendencies towards healthy and unhealthy food. Contrary to the hypothesis under test, results revealed a greater approach tendency towards healthy food in overweight individuals, as compared to healthy-weight individuals, whereas there were no group differences in behavioural approach-avoidance tendencies towards unhealthy food. These novel findings suggest that overweight individuals are characterised by an approach motivation for healthy food. We provide suggestions concerning how future researchers can build on these findings to test whether this approach tendency contributes to consumption behaviour in overweight individuals.

The association between pre-conception intuitive eating and gestational weight gain

PURPOSE

To determine if pre-conception intuitive eating, an adaptive eating behavior, was related to gestational weight gain (GWG) and the likelihood of exceeding GWG recommendations.

METHODS

This prospective survey study took place in an outpatient obstetric clinic. Participants completed the pre-conception Intuitive Eating Scale for Pregnancy during a prenatal check-up appointment and total GWG was collected from the medical record. The pre-conception Intuitive Eating Scale for Pregnancy assesses unconditional permission to eat, eating for physical rather than emotional reasons, and reliance on hunger and satiety to inform what, when, and how much to eat. Hierarchical linear multiple regression and logistic multiple regression analyses determined associations between pre-conception intuitive eating and GWG on the total sample and stratified by weight status (normal/underweight, overweight, and obese).

RESULTS

The majority of the sample (n = 253) was white, married, employed, had annual household income > $50,000, and had a college degree. No aspects of pre-conception intuitive eating predicted the likelihood of excess GWG. However, in the total sample, unconditional permission to eat (subscale) was inversely related to total GWG (B = -0.16, p < 0.05). Among women with obesity (n = 36), eating for physical rather than emotional reasons (subscale) was inversely related to total GWG (B = -0.47, p < 0.05).

DISCUSSION

Some aspects of intuitive eating during the pre-conception period were related to total GWG, particularly for women with obesity. However, intuitive eating scores did not increase or decrease the likelihood of excess GWG. More research is needed to understand the mechanisms for this association before clinical recommendations can be made.

LEVEL OF EVIDENCE

Level III (Evidence obtained from well-designed cohort or case-control analytic studies).

How interindividual differences shape approach-avoidance behavior: Relating self-report and diagnostic measures of interindividual differences to behavioral measurements of approach and avoidance

Responding to stimuli in ambiguous environments is partially governed by approach-avoidance tendencies. Imbalances in these approach-avoidance behaviors are implicated in many mental disorders including anxiety disorders, phobias and substance use disorders. While factors biasing human behavior in approach-avoidance conflicts have been researched in numerous experiments, a much-needed comprehensive overview integrating those findings is missing. Here, we systematically searched the existing literature on individual differences in task-based approach-avoidance behavior and aggregated the current evidence for the effect of self-reported approach/avoidance traits, anxiety and anxiety disorders, specific phobias, depression, aggression, anger and psychopathy, substance use and related disorders, eating disorders and habits, trauma, acute stress and, finally, hormone levels (mainly testosterone, oxytocin). We highlight consistent findings, underrepresented research areas and unexpected results, and detail the amount of controversy between studies. We discuss potential reasons for ambiguous results in some research areas, offer practical advice for future studies and highlight potential variables such as task-related researcher decisions that may influence how interindividual differences and disorders drive automatic approach-avoidance biases in behavioral experiments.